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Updated: May 30, 2026
Molecular and Immunologic Techniques in a Genetically Engineered Mouse Model of Gastrointestinal Stromal Tumor
Published on: May 2, 2022
Expression of DOG1, PDGFRA, and p16 in Gastrointestinal Stromal Tumors
Sung Hee Jung1, Kwang Sun Suh, Dae Young Kang
1Department of Internal Medicine, Eulji University Hospital, Eulji University College of Medicine, Daejeon, Korea.
Background/Aims:
The diagnosis of gastrointestinal stromal tumors (GIST) relies on the demonstration of KIT expression, but KIT expression is absent or reduced in approximately 15% of GIST.
Methods:
Eighty-one GISTs were diagnosed between January 1998 and December 2007 at the Department of Pathology at both Chungnam National University Hospital and Eulji University Hospital, Daejeon. Medical history, patient follow-up, and radiographic data were collected if available in the medical records. To determine diagnostic and prognostic markers for GISTs focused on PDGFRA mutation and clinicopathologic features, we analyzed 81 GIST cases for KIT, PDGFRA, DOG1, and p16 expression and for mutation of PDGFRA genes.
Results:
Among 81 GIST cases, 20 high risk cases (24.7%) were recurred or metastasized. Immunohistochemically, KIT was positive in 76 (93.8%), PDGFRA in 75 (92.7%), and DOG1 in 77 (95.1%). With a cutoff value of 50%, p16 expression was positive in 26 cases were positive (32.1%). A correlation between p16 expression or negative DOG1 expression and recurrence or metastasis was demonstrated (p<0.05). Four cases showed a missense mutation in exon 12 of PDGFRA gene, three of these were of epithelioid GISTs. Two cases showed a silent mutation in exon 18 of PDGFRA.
Conclusions:
These results indicate that the expression of DOG1 and PDGFRA is observed in a majority of GIST cases. Expression of p16 and negative DOG1 expression is predictive for development of recurrence and/or metastasis. Even though mutation of the PDGFRA gene is frequently seen in epithelioid GISTs, a clinicopathologic correlation was not demonstrated.
Insights
Diagnosis of gastrointestinal stromal tumors (GIST) can be challenging when KIT is not expressed. DOG1 and PDGFRA are highly expressed in GIST, and p16 expression predicts recurrence.
Area of Science:
- Gastrointestinal Pathology
- Oncology
- Molecular Diagnostics
Background:
- Gastrointestinal stromal tumors (GIST) diagnosis typically relies on KIT expression.
- KIT expression is reduced or absent in approximately 15% of GIST cases, necessitating alternative diagnostic markers.
- Identifying reliable diagnostic and prognostic markers for GIST is crucial.
Purpose of the Study:
- To investigate diagnostic and prognostic markers for GIST.
- To analyze KIT, PDGFRA, DOG1, and p16 expression in GIST.
- To examine PDGFRA gene mutations and their clinicopathologic correlation.
Main Methods:
- Analysis of 81 GIST cases diagnosed between 1998 and 2007.
- Immunohistochemical analysis for KIT, PDGFRA, DOG1, and p16 expression.
- PDGFRA gene mutation analysis (exons 12 and 18).
- Correlation of marker expression and mutations with clinicopathologic features and patient outcomes.
Main Results:
- KIT, PDGFRA, and DOG1 expression were positive in 93.8%, 92.7%, and 95.1% of GIST cases, respectively.
- p16 expression was observed in 32.1% of cases.
- A significant correlation was found between p16 expression or negative DOG1 expression and tumor recurrence or metastasis (p<0.05).
- PDGFRA mutations were identified in four cases, predominantly in epithelioid GISTs.
Conclusions:
- DOG1 and PDGFRA are expressed in the majority of GIST cases, serving as potential diagnostic markers.
- p16 expression and negative DOG1 expression are predictive of GIST recurrence and metastasis.
- While PDGFRA mutations are common in epithelioid GISTs, a clear clinicopathologic correlation was not established in this study.
